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Re-Anodizing or Epoxy Paint?

I work with a system that is housed in 7075 T6 Aluminum bottles and deployed in the deep ocean for a year at a time. The bottles are anodized (Type II) prior to deployment. This year, for the first time, we are looking at reusing the bottles as opposed to buying new ones. The old bottles have some nicking and white powder build-up on the outside, but are structurally sound. My question is is a corrosion-resistant epoxy painting sufficient for another year-long deployment, or would a stripping and re-anodizing of these bottles be required? Is there an epoxy paint that can hold up for a year in a pressurized salt water environment?

Scott Vann
1999

There are all kinds of marine paints that are available to the industry that will hold up to the environment your looking at, although they can tend to be expensive application. If your original process is to anodize and structurally will take stripping and replating, I would persue that method. Given a choice in our facility, with pricing and production in mind, I would strip and re-anodize. (We paint and anodize). Typically pricing structure for stripping may be 50% of anodizing cost so you will already be aware of cost.

Tim Martin
plating shop - Springfield, Massachusetts
1999